Biometric information registration apparatus, biometric information verification apparatus, biometric information registration/verification system, and biometric information registration program

ABSTRACT

In relation to a system which effects one-to-many authentication using biometric information; e.g., a fingerprint, an iris, voice, a facial image, a vascular pattern, a dynamic signature, or a keystroke, in order to significantly shorten the time required to verify registered feature information against input feature information, there is performed extraction of verification-purpose feature information and a plurality of types of verification-purpose attribute information from the biometric information about an object of authentication; computation of verification priority levels of a plurality of registration-purpose feature information items on the basis of registration-purpose attribute information and the verification-purpose attribute information, both being associated with the registration-purpose feature information items; and sequential verification of the verification-purpose feature information against registration-purpose feature information in accordance with a computed verification priority level, thereby specifying registration-purpose feature information matching said verification-purpose feature information from said plurality of registration-purpose feature information items.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/082,936, filed Mar. 18, 2005, now allowed, which is a continuationapplication, under 35 USC 111(a), of International ApplicationPCT/JP2003/000774, filed Jan. 28, 2003, the contents of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a technique suitable for use in asystem which authenticates the identity of a person by means ofbiometric information (biometrics information); for example, afingerprint, a palm pattern, an iris (iris muscle pattern), a voice, afacial image, a vascular pattern (a retinal vascular pattern, or a veinpattern), a dynamic signature, or a keystroke.

2. Description of the Related Art

Recently, in association with extensive introduction of a computer intosociety, attention has been focused on security. An ID card or apassword has hitherto been used as identification means when a personenters a computer room or makes use of a terminal. However, these meanshave many security problems.

For this reason, biometrics authentication utilizing biometricinformation about a human has recently been put into widespread use asidentification means which is more reliable than the ID card or thepassword. For instance, a fingerprint, a palm pattern, an iris, a facialimage, a voice, a vascular pattern, a dynamic signature, or a keystrokeis used as biometric information. Commercialization of a biometricauthentication technique utilizing a fingerprint among these pieces ofbiometric information has been pursued most extensively.

One-to-one authentication is usually used for fingerprintauthentication. Specifically, a subject of authentication enters an ID,such as a user name, and a fingerprint as well. Registered fingerprintdata, which have been registered beforehand, are read in associationwith the ID, and personal authentication is performed by verifying theregistered fingerprint data against the fingerprint data input by thesubject of authentication. However, such one-to-one authenticationrequires a keyboard and a keypad used for inputting an ID, as well as afingerprint sensor, thus requiring equipment cost. Further, there alsoexists strong demand for reducing the effort required when the subjectof authentication inputs an ID.

In contrast, an authentication technique for specifying a person byinputting only a fingerprint without inputting an ID is calledone-to-many authentication. According to this one-to-manyauthentication, the fingerprint data input by the subject ofauthentication are verified against all of the fingerprint data setsthat have been registered in advance to thus specify fingerprint datacoinciding with the input fingerprint data from among the registeredfingerprint data, thereby authenticating the subject. However, accordingto such one-to-many authentication, an increase in the number ofregistered fingerprint data sets naturally entails an increase in thetime required to verify all the registered fingerprint data againstinput fingerprint data. For this reason, shortening of the verificationtime is desired.

A technique for minimizing an increase in the verification time requiredfor one-to-many authentication is described in, e.g., Japanese PatentLaid-Open NO. 2002-133416 (hereinafter called Patent Document 1).According to the technique disclosed in Patent Document 1, attributeinformation (e.g., a fingerprint pattern type: see FIG. 6A to FIG. 6H)other than fingerprint data used for verification is detected. Theregistered fingerprint data have been classified in advance by means ofthe attribute information. Input fingerprint data are verified againstregistered fingerprint data that have the same attribute information (apattern type) as that obtained from the subject of authentication duringauthenticating operation. However, when, for instance, a fingerprintpattern type is used as attribute information, the registeredfingerprint data can be classified only into the number “n” offingerprint-type groups (e.g., eight types shown in FIGS. 6A to 6H) bymeans of such a technique. Therefore, the shortening of verificationtime is limited to a factor of only to about one-n^(th).

The present invention has been conceived in view of this problem andrealizes significant shortening of the time required to verify inputfeature information against registered feature information whenone-to-many authentication is performed through use of biometricinformation.

SUMMARY OF THE INVENTION

To achieve the object, a biometric information registration apparatus ofthe present invention is characterized by comprising: aregistration-purpose biometric information input section which samples,from a registered subject, registration-purpose biometric information tobe used for one-to-many authentication and inputs the sampledinformation; a registration-purpose feature information extractingsection which extracts registration-purpose feature information from theregistration-purpose biometric information input by theregistration-purpose biometric information input section; aregistration-purpose attribute information extracting section whichextracts, from the registration-purpose biometric information input bythe registration-purpose biometric information input section, aplurality of types of registration-purpose attribute informationdiffering from the registration-purpose feature information; and aregistration section for registering, in an associated manner, theregistration-purpose feature information extracted by theregistration-purpose feature information extracting section and theplurality of types of registration-purpose attribute informationextracted by the registration-purpose attribute information extractingsection.

A biometric information verification apparatus of the present inventionis also characterized by comprising: a verification-purpose biometricinformation input section which samples, from a subject ofauthentication, verification-purpose biometric information to be usedfor one-to-many authentication and which inputs the sampled information;a verification-purpose feature information extracting section whichextracts verification-purpose feature information from theverification-purpose biometric information input by theverification-purpose biometric information input section; averification-purpose attribute information extracting section whichextracts, from the verification-purpose biometric information input bythe verification-purpose biometric information input section, aplurality of types of verification-purpose information differing fromthe verification-purpose feature information; a verification prioritylevel computation section which computes priority levels of a pluralityof registration-purpose feature information items to be verified againstthe verification-purpose feature information extracted by theverification-purpose feature information extracting section, on thebasis of a plurality of types of registration-purpose attributeinformation associated with the plurality of registration-purposefeature information and the plurality of types of verification-purposeattribute information extracted by the verification-purpose attributeinformation extracting section; and a verification section whichsequentially verifies the verification-purpose feature informationextracted by the verification-purpose feature information extractingsection against the plurality of registration-purpose featureinformation in accordance with the verification priority level computedby the verification-priority computation section, to thus specifyinformation, which coincides with the verification-purpose featureinformation, from among the plurality of registration-purpose featureinformation items.

Further, a biometric information registration/verification system of thepresent invention is characterized by comprising a registration-purposebiometric information input section which samples, from a registeredsubject, registration-purpose biometric information to be used forone-to-many authentication and inputs the sampled information; aregistration-purpose feature information extracting section whichextracts registration-purpose feature information from theregistration-purpose biometric information input by theregistration-purpose biometric information input section; aregistration-purpose attribute information extracting section whichextracts, from the registration-purpose biometric information input bythe registration-purpose biometric information input section, aplurality of types of registration-purpose attribute informationdiffering from the registration-purpose feature information; aregistration section for registering, in an associated manner, theregistration-purpose feature information extracted by theregistration-purpose feature information extracting section and theplurality of types of registration-purpose attribute informationextracted by the registration-purpose attribute information extractingsection; a registration-purpose data storage section for storing theregistration-purpose feature information and the plurality of types ofregistration-purpose attribute information, which are registered in anassociated manner by the registration section; a verification-purposebiometric information input section which samples, from a subject ofauthentication, verification-purpose biometric information to be usedfor one-to-many authentication and which inputs the sampled information;a verification-purpose feature information extracting section whichextracts verification-purpose feature information from theverification-purpose biometric information input by theverification-purpose biometric information input section; averification-purpose attribute information extracting section whichextracts, from the verification-purpose biometric information input bythe verification-purpose biometric information input section, aplurality of types of verification-purpose information differing fromthe verification-purpose feature information; a verification prioritylevel computation section which computes priority levels of theregistration-purpose feature information items which are stored by theregistration-purpose data storage section to be verified against theverification-purpose feature information extracted by theverification-purpose feature information extracting section, on thebasis of the plurality of types of registration-purpose attributeinformation associated with the plurality of registration-purposefeature information and the plurality of verification-purpose attributeinformation extracted by the verification-purpose attribute informationextracting section; and a verification section which sequentiallyverifies the verification-purpose feature information extracted by theverification-purpose feature information extracting section against theplurality of registration-purpose feature information in accordance withthe verification priority level computed by the verification-prioritycomputation section, to thus specify information, which coincides withthe verification-purpose feature information, from among the pluralityof registration-purpose feature information items.

A biometric information registration program of the present invention isfor registering, into a registration-purpose data storage section,registration-purpose biometric information sampled from a subject ofregistration used for one-to-many authentication, the program beingcharacterized to cause a computer to act as a registration-purposefeature information extracting section; a registration-purpose attributeinformation extracting section; and a registration section.

According to the biometric information registration apparatus, thebiometric information verification apparatus, the biometric informationregistration/verification system, and the biometric informationregistration program, all pertaining to the present invention, whenone-to-many authentication is performed through use of biometricinformation, the verification priority levels of a plurality ofregistration-purpose feature information items are computed on the basisof the plurality of types of registration-purpose attribute informationitems associated with the registration-purpose feature information itemsand the plurality of types of verification-purpose attribute informationitems extracted from the biometric information about the subject ofauthentication. The verification-purpose feature information extractedfrom the biometric information about the subject of authentication issequentially verified against the registration-purpose featureinformation items in accordance with the computed verification prioritylevels, whereupon the registration-purpose feature informationcoinciding with the verification-purpose feature information isspecified among the plurality of registration-purpose featureinformation items.

As mentioned above, the higher the verification priority level of theregistration-purpose feature information determined on the basis of aplurality of types of attribute information, the higher the probabilityof matching feature information about the subject of authentication.Accordingly, verification-purpose feature information is verified inaccordance with a verification priority level without being verifiedagainst all of pieces of the registration-purpose feature informationwhen one-to-many verification is conducted. If a certain degree ofcoincidence is acquired, registration-purpose feature information aboutthe subject of verification can be determined. The time required forverification (the number of times verification is performed) can besignificantly curtailed, and an attempt can also be made to enhance theprecision of verification.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages will become apparent and morereadily appreciated from the following description of the embodiments,taken in conjunction with the accompanying drawings of which:

FIG. 1 is a block diagram showing a functional configuration of afingerprint data registration apparatus (a biometric informationregistration apparatus) serving as an embodiment of the presentinvention;

FIG. 2 is a block diagram showing a functional configuration of afingerprint data verification apparatus (a biometric informationverification apparatus) serving as the embodiment of the presentinvention;

FIG. 3 is a block diagram showing the hardware configuration of afingerprint authentication apparatus (a biometric informationregistration/verification apparatus) according to the embodiment;

FIG. 4 is a block diagram showing the hardware configuration of afingerprint authentication system (a biometric informationregistration/verification system) according to the embodiment;

FIG. 5 is a view for describing data contents in a registration-purposedata storage section of the embodiment;

FIGS. 6A to 6H are views showing specific examples of fingerprints fordescribing pattern types of fingerprints which serve as attributeinformation in the embodiment;

FIG. 7 is a view for describing the geometry of a finger which serves asattribute information of the embodiment;

FIGS. 8A, 9A, and 10A are views showing example fingerprint images offingers having different (low, medium, and high, respectively) moisturecontents;

FIGS. 8B, 9B, and 10B are graphs showing brightness of the examplefingerprint images in FIGS. 8A, 9A, and 10A, respectively;

FIG. 11 is a flowchart for describing fingerprint data registrationprocedures (operation of a fingerprint data registration apparatus) ofthe embodiment;

FIG. 12 is a flowchart for describing fingerprint data verificationprocedures (operation of a fingerprint data verification apparatus) ofthe embodiment;

FIGS. 13 and 14 are views for describing verification priority levelcomputation procedures of the present embodiment;

FIG. 15 is a flowchart for describing a modification of fingerprint dataverification procedures (operation of a fingerprint data verificationapparatus) of the embodiment;

FIG. 16 is a flowchart for describing a modification of verificationpriority level computation procedures according to the presentembodiment;

FIGS. 17 and 18 are views for describing a modification of verificationpriority level computation procedures of the present embodiment; and

FIG. 19 is a block diagram showing the functional configuration of amodification of the fingerprint data verification apparatus (biometricinformation verification apparatus) according to the embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Best Modes forImplementing the Invention

Embodiments of the present invention will be described hereinbelow byreference to the drawings.

[1] Hardware Configuration

The present invention is embodied as a fingerprint authenticationapparatus (a biometric information registration/verification apparatus)10 such as that shown in FIG. 3, or a fingerprint authentication system(a biometric information registration/verification system) such as thatshown in FIG. 4. FIGS. 3 and 4 are block diagrams showing the hardwareconfiguration of the fingerprint authentication apparatus and that ofthe fingerprint authentication system, respectively.

The fingerprint authentication apparatus 10 shown in FIG. 3 isconfigured as having the function of a fingerprint data registrationapparatus (a biometric information registration apparatus) to bedescribed later by reference to FIG. 1 and the function of a fingerprintdata verification apparatus (a biometric information verificationapparatus) to be described later by reference to FIG. 2. The fingerprintauthentication apparatus 10 is configured by connecting a fingerprintsensor 14 to a personal computer. This personal computer is a generalcomputer configured by mutually connecting at least a CPU 11, memory(ROM, RAM) 12, an input/output interface 13, and a storage device (ahard disk drive or the like) 15 by means of a bus 16. The fingerprintsensor 14 is also connected to the CPU 11 by way of the bus 16.

Here, any type of fingerprint sensor, such as an electrostaticcapacitive fingerprint sensor, an optical fingerprint sensor, or a heatsensitive fingerprint sensor, may be used as the fingerprint sensor 14.

A fingerprint registration/verification program (a biometric informationregistration/verification program) 15 a is stored in the storage device15 of the fingerprint authentication apparatus 10. As will be describedlater by reference to FIG. 5, the storage device 15 performs thefunction of a registration-purpose data storage section 15 b whichstores registered fingerprint data (registration-purpose featureinformation) extracted from a fingerprint registrant andregistration-purpose attribute information in association with an ID ofthe fingerprint registrant.

By means of reading and executing the fingerprintregistration/verification program 15 a stored in the storage device 15,the CPU 11 of the fingerprint authentication apparatus 10 fulfills thefunction of a fingerprint data registration apparatus (a biometricinformation registration apparatus) to be described later by referenceto FIG. 1 and a fingerprint data verification apparatus (a biometricinformation verification apparatus) to be described later by referenceto FIG. 2.

By means of the foregoing configuration, the fingerprint authenticationapparatus 10 shown in FIG. 3 performs registration operation (which willbe described in detail later) for registering and storing theregistration-purpose data extracted from the subject of registrationusing the fingerprint sensor 14 into the storage device 15 (theregistration-purpose data storage section 15 b). Further, thefingerprint authentication apparatus 10 performs verification processing(personal authentication which will be described in detail later) on thebasis of the verification-purpose data extracted from the subject ofauthentication using the fingerprint sensor 14 and registration-purposedata stored in the storage device 15 (the registration-purpose datastorage section 15 b).

The fingerprint authentication system (a biometric informationregistration/verification system) shown in FIG. 4 comprises afingerprint authentication apparatus 10A which performs the function ofa fingerprint data registration apparatus (a biometric informationregistration apparatus) to be described later by reference to FIG. 1; afingerprint authentication server 20 which performs the function of afingerprint data verification apparatus (a biometric informationverification apparatus) to be described later by reference to FIG. 2;and a LAN (Local Area Network) 30 which connects the fingerprintauthentication apparatus 10A to the fingerprint authentication server 20in a communicable manner.

In this fingerprint authentication system, the fingerprintauthentication apparatus 10A is configured by connecting the fingerprintsensor 14, such as an electrostatic fingerprint sensor, an opticalfingerprint sensor, or a heat-sensitive fingerprint sensor, to a commonpersonal computer which is built by connecting at least the CPU 11, thememory (ROM, RAM) 12, the input/output interface 13, and the storagedevice (a hard disk drive or the like) 15 by means of the bus 16, as isthe fingerprint authentication apparatus 10 shown in FIG. 3.

A fingerprint registration program (a biometric information registrationprogram) 15 c is stored in the storage device 15 of the fingerprintauthentication apparatus 10A. The CPU 11 of the fingerprintauthentication apparatus 10A fulfills the function of a fingerprint dataregistration apparatus (a biometric information registration apparatus)to be described later by reference to FIG. 1, by means of reading andexecuting the fingerprint registration program 15 c.

The fingerprint authentication server 20 is configured by connecting afingerprint sensor 24, such as an electrostatic capacitive fingerprintsensor, an optical fingerprint sensor, or a heat-sensitive fingerprintsensor, to a common server (a personal computer) which is built bymutually connecting at least a CPU 21, memory (ROM, RAM) 22, aninput/output interface 23, and a storage device (a hard disk drive orthe like) 25 by means of a bus 26.

A fingerprint verification program (a biometric information verificationprogram) 25 a is stored in the storage device 25 of the fingerprintverification server 20. Like the storage device 15 shown in FIG. 3, aswill be described later by reference to FIG. 5, the storage device 25performs the function of a registration-purpose data storage section 25b which stores registered fingerprint data (registration-purpose featureinformation) extracted from the fingerprint registrant andregistration-purpose attribute information in association with the ID ofthe fingerprint registrant.

By means of reading and executing the fingerprintregistration/verification program 25 a stored in the storage device 25,the CPU 21 of the fingerprint authentication apparatus 20 fulfills thefunction of a fingerprint data verification apparatus (a biometricinformation verification apparatus) to be described later by referenceto FIG. 2.

By means of the foregoing configuration, the fingerprint authenticationapparatus 10A shown in FIG. 4 performs registration operation (whichwill be described in detail later) for registering and storing theregistration-purpose data extracted from the subject of registrationusing the fingerprint sensor 14 into the storage device 25 (theregistration-purpose data storage section 25 b) of the fingerprintauthentication server 20 by way of the LAN 30.

Further, when personal authentication is performed, the subject ofauthentication inputs a fingerprint image by use of the fingerprintsensor 14 connected to the fingerprint authentication apparatus 10A orthe fingerprint sensor 24 connected to the fingerprint authenticationserver 20 and sends the fingerprint image to the fingerprintauthentication server 20. The fingerprint authentication server 20performs verification processing (which will be described in detaillater) for verifying the verification-purpose data extracted from thefingerprint image of the subject of authentication against the dataregistered in the storage device 25 (the registration-purpose datastorage section 25 b).

[2] Functional Configuration

The functional configuration of a fingerprint data registrationapparatus (a biometric information registration apparatus) of thepresent embodiment and that of the fingerprint data verificationapparatus (a biometric information verification apparatus), which areimplemented by the hardware configuration shown in FIGS. 3 and 4, willbe described by reference to the block diagrams shown in FIGS. 1 and 2.Unparenthesized reference numerals in FIGS. 1 and 2 and the followingdescriptions are assigned to the functional configurations realized bythe hardware configuration (the fingerprint authentication apparatus 10)shown in FIG. 3. Parenthesized reference numerals are assigned to thefunctional configuration realized by the hardware configuration (afingerprint authentication system) shown in FIG. 4. When unparenthesizedreference numerals and parenthesized reference numerals are identicalwith each other, in some cases inscription of the parenthesizedreference numerals is omitted.

[2-1] Functional Configuration of the Fingerprint Data RegistrationApparatus

The fingerprint data registration apparatus of the present embodimentshown in FIG. 1 is configured from the fingerprint sensor 14 (14), aregistration-purpose fingerprint data extracting section 11 a (11 a), aregistration-purpose attribute information extracting section 11 b (11b); a registration section 11 e (11 e); and a registration-purpose datastorage section 15 b (25 b). The function of the registration-purposefingerprint data extracting section 11 a (11 a), that of theregistration-purpose attribute information extracting section 11 b (11b), and that of the registration section 11 e (11 e) can be implementedby means of the CPU 11 executing the fingerprintregistration/verification program 15 a (the fingerprint registrationprogram 15 c).

As mentioned previously, the fingerprint sensor 14 is an electrostaticcapacitive fingerprint sensor, an optical fingerprint sensor, or aheat-sensitive fingerprint sensor and functions as aregistration-purpose biometric information input section (a fingerprintinformation input section) which samples from a subject of registrationa registration-purpose fingerprint image as registration-purposebiometric information to be used for one-to-many authentication andinputs the sampled image to the CPU 11.

The registration-purpose fingerprint data extracting section (theregistration-purpose feature information extracting section) 11 a is forextracting information about feature points (minutiae) of ridges in afingerprint image from a registration-purpose fingerprint image input byway of the fingerprint sensor 14 as the registered fingerprint data(registration-purpose feature information) through use of the Minutiamethod disclosed in, e.g., Japanese Patent Laid-Open NO. HEI 11-195119.Specifically, the information about feature points includes thepositions, types (end points and bifurcation points), directions of thefeature points, and positions of feature points projected as a result ofthe feature points being projected on the ridges.

The registration-purpose attribute information extracting section 11 bextracts, from the registration-purpose fingerprint image input by wayof the fingerprint sensor 14, a plurality of types ofregistration-purpose attribute information items which are differentfrom the registered fingerprint data extracted by theregistration-purpose fingerprint data extracting section 11 a. Theregistration-purpose attribute information extracting section 11 b hasattribute information extracting sections 11 b-1, 11 b-2, 11 b-3, . . .which extract attribute information for each type ofregistration-purpose attribute information to be extracted.

From the following items (1) to (7), two or more are extracted asregistration-purpose attribute information:

(1) The pattern type of a fingerprint in a registration-purposefingerprint image;

(2) The geometry of a finger in the registration-purpose fingerprintimage;

(3) The number of feature points extracted from the registration-purposefingerprint image;

(4) The volume of registered fingerprint data (registration-purposefeature information) extracted from the registration-purpose fingerprintimage;

(5) A processing time (computing time) required to extract theregistered fingerprint data by means of the registration-purposefingerprint data extracting section 11 a;

(6) The moisture content of the finger surface in theregistration-purpose fingerprint image; and

(7) The input environment information about the registration-purposefingerprint image.

Here, the pattern types of fingerprints in the registration-purposefinger print images (1) are eight types (i.e., a right central pocketloop, a left central pocket loop, a double loop, a plain arch, a plainwhorl, a left loop, a right loop, and a tented arch) such as those shownin, e.g., FIGS. 6A to 6H. A technique for extracting these pattern typesis disclosed in, e.g., Japanese Patent Laid-Open NO. 2002-133416. FIGS.6A to 6H are views showing specific fingerprint examples for describingpattern types of fingerprints as attribute information of the presentembodiment.

The geometry of the finger (2) is defined as shown in, e.g., FIG. 7.Specifically, as shown in FIG. 7, the geometry of the finger remainingin touch with a sensor face of the fingerprint sensor 14 is defined andextracted as a rectangle which has a lateral length “X” and alongitudinal length “y” and circumscribes the fingerprint image. FIG. 7is a view for describing the geometry of a finger as attributeinformation in the embodiment.

The number of feature points (3) is acquired by measuring the featurepoints extracted from the registered fingerprint image by theregistration-purpose fingerprint data extracting section 11 a throughuse of the Minutia method.

Similarly, the volume of data (4) is obtained by measuring theregistered fingerprint data extracted by the registration-purposefingerprint data extracting section 11 a through use of the Minutiamethod. The processing time (5) is acquired by counting the timerequired by the registration-purpose fingerprint data extracting section11 a to extract the registered fingerprint data through use of theMinutia method.

When the electrostatic capacitive fingerprint sensor is used as thefingerprint sensor 14, the brightness of an output image changes inaccordance with the moisture content of the surface of the finger. Here,FIGS. 8A, 9A, and 10A are views showing fingerprint image examples offingers having different moisture contents (low, medium, and high,respectively). FIGS. 8B, 9B, and 10B are graphs showing brightness ofthe fingerprint image examples shown in FIGS. 8A, 9A, and 10A,respectively. In the case of a finger having a low moisture content, afingerprint image having a low brightness level, such as that shown inFIGS. 8A and 8B, is sampled. In contrast, in the case of a finger havinga high moisture content, a fingerprint image having a high brightnesslevel, such as those shown in FIGS. 10A and 10B, is sampled. In the caseof a finger having a medium moisture content, a fingerprint image havingan intermediate (standard) brightness level, such as those shown inFIGS. 9A and 9B, is sampled. When the fingerprint image is sampled bymeans of the electrostatic capacitive fingerprint sensor 14, the outputgain of the fingerprint sensor 14 is generally compensated in accordancewith the brightness level in order to acquire a bright fingerprint image(specifically, a fingerprint image having an intermediate brightnesslevel such as that shown in FIGS. 9A and 9B). The amount of gaincompensation computed during such a compensating operation correspondsto the moisture content of the finger surface. The moisture content ofthe finger surface (6) can be extracted as the amount of gaincompensation.

In the fingerprint authentication system such as that shown in FIG. 4,when a user registers a finger in the fingerprint authentication server20 over the Internet from a personal computer (corresponding to thefingerprint authentication apparatus 10A in FIG. 4) of the user,registration-purpose attribute information can be acquired from theinput environment information about the registration-purpose fingerprintimage (7). Specifically, the input environment information is the IP(Internet Protocol) address of the personal computer or the user name ofa logged-in user.

The registration section 11 e registers, in the registration-purposedata storage section 15 b (25 b), the registered fingerprint dataextracted by the registration-purpose fingerprint data extractingsection 11 a and a plurality of types of registration-purpose attributeinformation extracted by the registration-purpose attribute informationextracting section 11 b in an associated manner. More specifically, asshown in FIG. 5, in the registration-purpose data storage section 15 b(25 b), the registered fingerprint data extracted from the registeredfingerprint image of the fingerprint registrant and a plurality of typesof the registration-purpose attribute information (three types in FIG.5) are compiled into a database and then registered and stored in theform of a table in association with the ID of the fingerprintregistrant.

Here, FIG. 5 is a view for describing data contents in theregistration-purpose data storage section 15 b (25 b). In the embodimentshown in FIG. 5, the IDs (ID1, ID2, and ID3) of the respectivefingerprint registrants are associated with the registered fingerprintdata (fingerprint data 1, fingerprint data 2, and fingerprint data 3),and three types of attribute information “a” (e.g., a pattern type:attributes a1, a2, and a3), “b” (e.g., the number of feature points;attributes b1, b2, and b3), or “c” (e.g., moisture contents; attributesc1, c2, and c3).

In the fingerprint authentication apparatus 10 shown in FIG. 3, theregistration section 11 e registers registered fingerprint data and aplurality of types of registration-purpose attribute information intothe storage device 15 (the registration-purpose data storage section 15b) built in the same personal computer. In the fingerprintauthentication system shown in FIG. 4, the registration section 11 eregisters the registered fingerprint data and a plurality of types ofregistration-purpose attribute information in the fingerprintauthentication server 20 and the storage device 25 (theregistration-purpose data storage section 25 b) by way of acommunication line (LAN 30).

Operation of the fingerprint data registration apparatus of thepreviously-described embodiment (fingerprint data registrationprocedures) will be described later by reference to FIG. 11.

[2-2] Functional Configuration of the Fingerprint Data VerificationApparatus

The fingerprint data verification apparatus of the embodiment shown inFIG. 2 comprises the fingerprint sensor 14 (24); theverification-purpose fingerprint data extracting section 11 a (21 a);the verification-purpose attribute information extracting section 11 b(21 b); a registration-purpose data read control section 11 c (21 c); averification section 11 d (21 d); a verification result output section13 (23); and the registration-purpose data storage section 15 b (25 b).The function of the verification-purpose fingerprint data extractingsection 11 a (21 a), that of the verification-purpose attributeinformation extracting section 11 b (21 b), that of theregistration-purpose data read control section 11 c (21 c), and that ofthe verification section 11 d (21 d) are fulfilled by means of the CPU11 (21) executing the fingerprint registration/verification program 15 a(the fingerprint verification program 25 a).

As mentioned previously, the fingerprint sensor 14 (24) is anelectrostatic capacitive sensor, an optical sensor, or a heat-sensitivesensor, and functions as a verification-purpose biometric informationinput section (a fingerprint information input section) which samples,from a subject of authentication, a verification-purpose fingerprintimage used as verification-purpose biometric information for effectingone-to-many authentication and inputs the sampled image to the CPU 11(21).

The verification-purpose fingerprint data extracting section (averification-purpose feature information extracting section) 11 a (21 a)is for extracting verification fingerprint data (verification-purposefeature information) from the verification-purpose fingerprint imageinput by way of the fingerprint sensor 14 (24) through use of theMinutia method disclosed in, e.g., Japanese Patent Laid-Open NO. HEI11-195119. The verification fingerprint data to be extracted areidentical in type with the registered fingerprint data previouslyregistered in the registration-purpose data storage section 15 b (25 b).In the embodiment, the verification fingerprint data correspond toinformation about feature points (minutiae) of ridges in the fingerprintimage [the positions, types (end points and bifurcation points), anddirections of the feature points and positions of the feature pointsobtained as a result of the features points being projected on theridges].

The verification-purpose attribute information extracting section 11 b(21 b) is for extracting, from the verification-purpose fingerprintimage input by the fingerprint sensor 14 (24), a plurality of types ofverification-purpose attribute information which are different from theverification fingerprint data extracted from the verification-purposefingerprint data extracting section 11 a (21 a). Theverification-purpose attribute information extracting section 11 b (21b) is provided with the attribute information extracting sections 11 b-1(21 b-1), 11 b-2 (21 b-2), 11 b-3 (21 b-3), . . . for extractingattribute information for each type of verification-purpose attributeinformation to be extracted.

For instance, among the information items (1) to (7) provided below,attribute information items which are the same in type with theregistration-purpose attribute information extracted by theregistration-purpose attribute information extracting section 11 a shownin FIG. 1 are extracted as the verification-purpose attributeinformation.

(1) The pattern type of a fingerprint in a verification-purposefingerprint image;

(2) The geometry of a finger in the verification-purpose fingerprintimage;

(3) The number of feature points extracted from the verification-purposefingerprint image;

(4) The volume of registered fingerprint data (verification-purposefeature information) extracted from the verification-purpose fingerprintimage;

(5) A processing time (computing time) required to extract theregistered fingerprint data by means of the verification-purposefingerprint data extracting section 11 a (21 a);

(6) The moisture content of the finger surface in theverification-purpose fingerprint image; and

(7) The input environment information about the verification-purposefingerprint image.

A method for extracting the verification-purpose attribute informationitems (1) to (7) is the same as the method for extracting theregistration-purpose attribute information items (1) to (7) which hasalready been described in connection with item [2-1], and hence itsexplanation is omitted.

The registration-purpose data read control section 11 c (21 c) has thefunction of a verification priority level computation section to bedescribed later. In accordance with the verification priority levelcomputed by the function of the verification priority level computationsection, the registration-purpose data read control section 11 c (21 c)sequentially reads the registered fingerprint data from theregistration-purpose data storage section 15 b (25 b) and inputs thethus-read data to the verification processing section 11 d (21 d).

The verification priority level computation section is for computingverification priority levels of a plurality of registered fingerprintdata sets previously stored in the registration-purpose data storagesection 15 b (25 b) to be verified against the verification fingerprintdata extracted by the verification-purpose fingerprint data extractingsection 11 a (21 a), in accordance with the plurality of types ofregistration-purpose attribute information previously stored in theregistration-purpose data storage section 15 b (25 b) associated withthe registered fingerprint data and a plurality of types ofverification-purpose attribute information items extracted by theverification-purpose attribute information extracting section 11 b (21b). The verification priority level computation section computes anddetermines the verification priority level by means of any one of thefollowing two types of technique (1), (2).

Technique (1): First, the plurality of types of verification-purposeattribute information items are compared with the plurality of types ofregistration-purpose attribute information items associated with therespective registered fingerprint data sets, to thus determine whetheror not a coincidence exists between the information items. Of theplurality of types of registration-purpose attribute information itemsassociated with the registered fingerprint data, weighting coefficientshave been assigned in advance to registration-purpose information itemsdetermined to coincide with the verification-purpose attributeinformation items. The weighting coefficients are summed for eachregistered fingerprint data set. The resultant sum value is computed asan attribute information coincidence score of the registered fingerprintdata. Thus, the verification priority level is determined in accordancewith the magnitude of the attribute information coincidence computed foreach registered fingerprint data set. This technique (1) will bedescribed specifically by reference to FIGS. 13 and 14.

Technique (2): Like Technique (1), a determination is made as to whetheror not coincidence exists between the plurality of types ofverification-purpose attribute information items and the plurality oftypes of registration-purpose attribute information items associatedwith the respective registered fingerprint data sets, by comparing theinformation items with each other. Verification priority levels aredetermined in accordance with the priority levels previously imparted tothe registration-purpose attribute information items, which aredetermined to coincide with the verification-purpose attributeinformation, among the plurality of types of registration-purposeattribute information items. The registered fingerprint data are sortedin accordance with the verification priority levels. This technique (2)will be described specifically by reference to FIGS. 16 to 18.

The verification processing section (verification section) 11 d (21 d)sequentially verifies the verification fingerprint data extracted by theverification-purpose fingerprint data extracting section 11 a (21 a) inaccordance with the verification priority levels computed by thefunction of the verification priority level computing section, therebyspecifying the fingerprint data coinciding with the verificationfingerprint data from the plurality of registered fingerprint data sets,and reports the result of verification (the result of specification) tothe verification result output section 13 (23).

In reality, the verification processing section 11 d (21 d) sequentiallyverifies the verification fingerprint data against the registeredfingerprint data read from the registration-purpose data storage section15 b (25 b) by means of the registration-purpose data read controlsection 11 c (21 c), thereby automatically effecting verificationcomplying with the verification priority level.

For example, a common method, such as the Minutia method or the patternpatching method, is used as a fingerprint verification scheme of theverification processing section 11 d (21 d). However, the method is notlimited particularly to these methods, and any fingerprint verificationmethod may be adopted.

The verification processing section 11 d (21 d) specifies verificationfingerprint data by means of any one of the following two types oftechniques (i), (ii).

Technique (i): Verification of the verification fingerprint data againstthe respective registered fingerprint data sets is completed uponappearance of the registered fingerprint data set coinciding with theverification fingerprint data while satisfying predetermined standards.The registered fingerprint data set satisfying the predeterminedstandards is specified as coinciding with the verification fingerprintdata. This technique (i) will be specifically described by reference toFIG. 12.

Technique (ii): The registered fingerprint data sets whose verificationpriority levels computed by means of the registration-purpose data readcontrol section 11 c (21 c) are higher than a reference level aregrouped as a verification object group. The verification fingerprintdata are verified against all of the registered fingerprint data setsbelonging to the verification object group. The registered fingerprintdata set that is determined to have the highest degree of coincidence asa result of verification is specified as information coinciding with theverification-purpose feature information. This technique (ii) will bespecifically described by reference to FIG. 15.

The verification result output section 13 (23) is realized by theinput/output interface 13 (23) shown in FIG. 3 (FIG. 4), and outputs theverification result (the specification result) reported by theverification processing section 11 d (21 d).

In the fingerprint authentication apparatus 10 shown in FIG. 3, thefunction of the registration-purpose biometric information input sectionand the function of the verification-purpose biometric information inputsection are realized by the single fingerprint sensor (the biometricinformation input section) 14. The function of the registration-purposefeature information extracting section and the function of theverification-purpose feature information extracting section are realizedby the single fingerprint data extracting section (the featureinformation extracting section) 11 a. The function of theregistration-purpose attribute information extracting section and thefunction of the verification-purpose attribute information extractingsection are realized by the single attribute information extractingsection 11 b.

[2-3] Others

The previously-described fingerprint/verification program (the biometricinformation registration/verification program) 15 a, the fingerprintregistration program (the biometric information registration program) 15c, and the fingerprint verification program (the biometric informationverification program) 25 a are provided while being recorded on acomputer-readable recording medium; e.g., a flexible disk, a CD-ROM, aCD-R, a CD-RW, a DVD, or the like. In this case, the computer (CPU 11,21) reads the programs 15 a, 15 c, and 25 a from the recording mediumand stores the programs in an internal storage device or transfers theprograms to an external storage device, to thus execute the programs.The programs 15 a, 15 c, and 25 a may be recorded in a storage device(recording medium); e.g., a magnetic disk, an optical disk, or amagneto-optical disk, and provided to the computer (CPU 11) from thestorage device over a communications line.

Here, the computer is a concept encompassing hardware and an operatingsystem and signifies hardware which operates under control of theoperating system. Moreover, when the operating system is not requiredand when hardware is operated by means of only an application program,the hardware itself corresponds to a computer. The hardware is equippedwith, at least, a microprocessor such as a CPU, and means for reading acomputer program recorded on a recording medium. The application programincludes a program code for causing the computer to implement thefingerprint authentication apparatus 10, 10A and the fingerprintauthentication server 20. A part of the functions may be embodied by theoperating system rather than by the application program.

In addition to the previously-described flexible disk, the CD-ROM, theCD-R, the CD-RW, the DVD, the magnetic disk, the optical disk, and themagneto-optical disk, various computer-readable mediums, such as an ICcard, an ROM cartridge, a magnetic tape, a punch card, an internalstorage device (memory such as RAM or ROM) in a computer, an externalstorage device, or a printed product on which is printed a code such asa barcode, can be utilized as the recording medium of the presentembodiment.

[3] Operation of the Embodiment

Operation of the previously-described fingerprint authentication systemof the embodiment (the fingerprint data registration apparatus and afingerprint data verification apparatus) will be described by referenceto FIGS. 11 to 18.

[3-1] Fingerprint Data Registration Procedures

Operation of the fingerprint data registration apparatus (i.e.,fingerprint data registration procedures) shown in FIG. 1 will bedescribed in accordance with the flowchart (steps S11 to S17) shown inFIG. 11.

When the registered fingerprint data to be used for one-to-manyauthentication are registered, the subject of registration inputs afingerprint image by way of the fingerprint sensor 14 (step S11).Registered fingerprint data are extracted from the input fingerprintimage by means of the registration-purpose fingerprint data extractingsection 11 a (step S12). A plurality of registration-purpose attributeinformation items are extracted by means of the registration-purposeattribute information extracting section 11 b (steps S13 to S16).

First, a first item of attribute information (an attribute item) iscalled up at the time of registration of the registration-purposeattribute information (step S13). Registration-purpose attributeinformation corresponding to the item is extracted by the attributeextracting section 11 b-1 (step S14), to thus determine whether or notthe attribute item is the final attribute item (step S15). If theattribute item is not the final attribute item (when NO is selected instep S15), the next attribute item will be called up (step S16).Registration-purpose attribute information corresponding to theattribute item is extracted by means of the attribute extractingsections 11 b-2, 11 b-3, . . . (step S14).

When all of the plurality of types of previously-designatedregistration-purpose attribute information items have been extractedthrough repetition of these extracting operations (when YES is selectedin step S15), the registration section 11 e associates the registeredfingerprint data extracted by the registration-purpose fingerprint dataextracting section 11 a and the plurality of types ofregistration-purpose attribute information items extracted by theregistration-purpose attribute information extracting section 11 b withthe ID of the subject of registration, whereby the data and informationare registered as a database of table format, such as that shown in FIG.5, in the registration-purpose data storage section 15 b (25 b) (stepS17).

[3-2] Fingerprint Data Verification Procedures

In accordance with the flowchart (steps S21 to S35) shown in FIG. 12,operation of the fingerprint data verification apparatus shown in FIG. 2(i.e., fingerprint data verification procedures) will be described.

When verification is performed, the subject of authentication inputs afingerprint image by way of the fingerprint sensor 14 (24) (step S21).Verification fingerprint data are extracted from the input fingerprintimage by means of the verification-purpose fingerprint data extractingsection 11 a (21 a), and the extracted fingerprint data are input to theverification processing section 11 d (21 d) (step S22). Further, aplurality of verification-purpose attribute information items areextracted by means of the verification-purpose attribute informationextracting section 11 b (21 b) (step S23 to S26).

At the time of extracting of the verification-purpose attributeinformation, the first item of the attribute information (attributeitem) is called up (step S23), and the verification-purpose attributeinformation corresponding to the item is extracted by the attributeextracting section 11 b-1 (21 b-1) (step S24), thereby determiningwhether or not the attribute item is final (step S25). If the attributeitem is not the final attribute item (when NO is selected in step S25),the next attribute item is called up (step S26). Theverification-purpose attribute information corresponding to theattribute item is extracted by the attribute extracting sections 11 b-2(21 b-2), 11 b-3 (21 b-3), . . . (step S24).

When all of the plurality of types of previously-designatedverification-purpose attribute information items have been extractedthrough repetition of these extracting operations (when YES is chosen instep S25), a determination is made as to whether or not coincidenceexists between the attribute information items, through use of Technique(1) by means of the function of the registration-purpose data readcontrol section 11 c (21 c) serving as the verification prioritycomputation section, and an attribute information coincidence score iscomputed (step S27, which will be described in detail later).Verification priority levels of the plurality of sets of registeredfingerprint data are computed and determined (step S28).

The registered fingerprint data are sequentially read from theregistration-purpose data storage section 15 b (25 b) by theregistration-purpose data read control section 11 c (21 c) in accordancewith the verification priority level, and the thus-read data are inputto the verification processing section 11 d (21 d). The verificationprocessing section 11 d (21 d) specifies fingerprint data coincidingwith the verification fingerprint data from the plurality of registeredfingerprint data sets, through use of Technique (i) in the followingmanner (steps S29 to S33).

First, the registration-purpose data read control section 11 c (21 c)reads, from the registration-purpose data storage section 15 b (25 b),the first registered fingerprint data set; that is, the registeredfingerprint data having the highest attribute information coincidencescore and the highest verification priority level (step S29). Theverification processing section 11 d (21 d) verifies the firstregistered fingerprint data against the verification fingerprint dataextracted by the verification-purpose fingerprint data extractingsection 11 a (21 a) (step S30).

On the basis of the result of verification, the verification processingsection 11 d (21 d) determines whether or not the verificationfingerprint data and the registered fingerprint data satisfy thepredetermined standards; that is, whether or not the fingerprint of thesubject of authentication is the fingerprint of the person who hasregistered the registered fingerprint data (step S31).

When the fingerprint is determined not to be the fingerprint of theperson (when NO is selected in step S31), a determination is then madeas to whether or not the registered fingerprint data set—which is theobject of verification—is a final fingerprint data set (step S32). Whenthe registered fingerprint data set is determined not to be finalfingerprint data set (when NO is selected in step S32), theregistration-purpose data read control section 11 c (21 c) reads theregistered fingerprint data set having the next highest verificationpriority level from the registration-purpose data storage section 15 b(25 b) (step S33), and processing analogous to that mentioned previously(steps S30 to S32) is then performed.

When the registered fingerprint data set is determined to thefingerprint of the person in step S31 (when YES is selected), thefingerprint data set coinciding with the verification fingerprint datais specified among the plurality of sets of registered fingerprint data.The verification result indicating that the subject of authentication isthe registered person is output from the verification result outputsection 13 (23) (step S34), whereupon verification processing isterminated.

As mentioned previously, the verification processing section 11 a (21 a)terminates verification of the verification fingerprint data against therespective registered fingerprint data sets upon appearance of theregistered fingerprint data coinciding with the verification fingerprintdata set while satisfying the predetermined standards has appeared; thatis, when YES is selected in step S31, and specifies the registeredfingerprint data set satisfying the predetermined standards asfingerprint data coinciding with the verification fingerprint data.Specifically, in the verification procedures shown in FIG. 12, theregistered fingerprint data are verified against the verificationfingerprint data according to the verification priority levels. Theregistered fingerprint data having first satisfied the verificationstandards are approved as belonging to the subject of authentication,thereby identifying the subject of authentication as the registrant.

In contrast, when the registered fingerprint data are determined to befinal fingerprint data in step S32 (when YES is selected), specificationof fingerprint data coinciding with the verification fingerprint datawhile satisfying the predetermined standards among the plurality of setsof registered fingerprint data has ended in failure. A result indicatingthat the fingerprint of the subject of authentication is not registeredas registered fingerprint data (a result indicating that identificationhas ended in failure) is output from the verification result outputsection 13 (23) (step S35), and verification processing is completed.

[3-3] Verification Priority Level Computation Procedures

By reference to FIGS. 13 and 14, the verification priority levelcomputation procedures of the embodiment; that is, processing proceduresto be performed by the function of the verification priority levelcomputation section of the registration-purpose data read controlsection 11 c (21 c) in step S27 in FIG. 12, will be described in moredetail.

Here, as shown in FIG. 13, data analogous to those described inconnection with the embodiment shown in FIG. 5 are assumed to beregistered in the registration-purpose data storage section 15 b (25 b).Specifically, the registered fingerprint data (fingerprint data 1,fingerprint data 2, and fingerprint data 3), the attribute information“a” (e.g., a pattern type: attributes a1, a2, and a3), theregistration-purpose attribute information “b” (e.g., the number offeature points; attributes b1, b2, and b3), and the registration-purposeattribute information “c” (e.g., moisture contents; attributes c1, c2,and c3) are registered in association with the IDs (ID1, ID2, and ID3)of the respective fingerprint registrants. As shown in FIG. 13,weighting coefficients 3, 2, 1 are previously imparted to theregistration-purpose attribute information items “a,” “b,” and “c.”These weighting coefficients are determined in consideration of thedetection accuracy of the respective attribute information items,variations in data, or the like.

A determination as to coincidence/noncoincidence is rendered bycomparing the verification-purpose attribute information with theregistration-purpose attribute information. Consequently, threeattributes a2, b2, and c2 pertaining to ID2 are assumed to coincide withthe verification-purpose attribute information items “a,” “b,” and “c.”Two attributes a1 and c1 pertaining to ID1 are assumed to coincide withthe verification-purpose attribute information “a” and “c.” An attributeb3 pertaining to ID3 is assumed to coincide with theverification-purpose attribute information “b.” In FIG. 14, anunderlined attribute is assumed to be an attribute having coincided withthe verification-purpose attribute information.

Subsequently, the registration-purpose data read control section 11 c(21 c) sums the weighting coefficients previously imparted to theattributes having coincided with the verification-purpose attributeinformation, and computes the sum value as an attribute coincidencescore of the respective set of registered fingerprint data. Accordingly,in the embodiment shown in FIG. 14, the attribute coincidence score ofthe fingerprint data 2 pertaining to ID2 comes to 3+2+1=6. The attributecoincidence score of the fingerprint data 1 pertaining to ID1 comes in3+1=4. The attribute coincidence score of the fingerprint data 3pertaining to ID3 comes to 2. In FIG. 14, data are sorted in decreasingorder of the attribute coincidence scores computed in the mannermentioned previously. In the embodiment, the data having higherattribute coincidence score are taken as having a higher verificationpriority level.

[3-4] Modification of Fingerprint Data Verification Procedures

In accordance with the flowchart (steps S21 to S26 and S50 to S62) shownin FIG. 15, a modification of operation of the fingerprint dataverification apparatus shown in FIG. 2 will be described.

Even in this modification, as in the case of the operation (procedures)previously described by reference to FIG. 12, the subject ofauthentication inputs a fingerprint image by way of the fingerprintsensor 14 (24) (step S21). Verification fingerprint data are extractedfrom the input fingerprint image by means of the verification-purposefingerprint data extracting section 11 a (21 a), and the extractedfingerprint data are input to the verification processing section 11 d(21 d) (step S22). Further, a plurality of verification-purposeattribute information items are extracted by means of theverification-purpose attribute information extracting section 11 b (21b) (step S23 to S26).

When all of the plurality of types of previously-designatedverification-purpose attribute information items have been extracted(when YES is selected in step S25), a determination is made as towhether or not coincidence exists between the attribute informationitems through use of Technique (2) by means of the function of theregistration-purpose data read control section 11 c (21 c) serving asthe verification priority computation section. Verification prioritylevels of a plurality of registration-purpose fingerprint data sets arecomputed (the registered fingerprint data sets are actually sorted) onthe basis of the result of coincidence determination (step S50).

The verification processing section 11 d (21 d) groups, as averification object group, the registered fingerprint data sets (theregistered fingerprint data sets given higher levels as a result ofsorting of the registered fingerprint data) whose verification prioritylevels computed by the registration-purpose data read control section 11c (21 c) are higher than the standard levels. The number of registeredfingerprint data sets belonging to the verification object group is setas a preset value “an” (step S51).

Subsequently, the registration-purpose data read control section 11 c(21 c) sequentially reads the registered fingerprint data sets belongingto the verification object group from the registration-purpose datastorage section 15 b (25 b) and inputs the thus-read data sets into theverification processing section 11 d (21 d). The verification processingsection 11 d (21 d) specifies the fingerprint data coinciding with theverification fingerprint data among the plurality of registeredfingerprint data through use of Technique (ii) in the following manner(steps S52 to S60).

First, the registration-purpose data read control section 11 c (21 c)reads, from the registration-purpose data storage section 15 b (25 b),the first registered fingerprint data set; that is, the registeredfingerprint data set having the highest attribute informationcoincidence score and the highest verification priority level (stepS52). After initial setting (N=1) has been performed (step S53), theverification processing section 11 d (21 d) verifies the firstregistered fingerprint data set against the verification fingerprintdata extracted by the verification-purpose fingerprint data extractingsection 11 a (21 a) (step S54).

A determination is then made as to whether or not the coincidence scoreshowing the degree of coincidence existing between the registeredfingerprint data and the verification-purpose fingerprint data set isthe highest score (larger than the highest coincidence score acquiredpreviously) (step S55). When the coincidence score is the highest score(when YES is selected in step S55; the coincidence score naturallybecome the highest for the first registered fingerprint data), thecoincidence score is held as the highest score (step S56).

When the coincidence score acquired this time is determined not to bethe highest score (when NO is selected in step S56) or after the highestscore is held, a determination is made as to whether or not N is equalto or greater than the preset value “n” set in step S51; that is,whether or not verification of the verification fingerprint data againstall of the registered fingerprint data sets belonging to theverification object group has been completed (Step S57).

When N is smaller than the preset value “n” (when NO is selected in stepS57), N+1 is set as N (step S58), and the registration-purpose data readcontrol section 11 c (21 c) reads the next registered fingerprint dataset belonging to the verification-object group from theregistration-purpose data storage section 15 b (25 b) (step S59), andprocessing analogous to that mentioned previously is performed (stepsS54 to S57).

When N is determined to be equal to the preset value “n” or higher instep S57; that is, when verification of the verification fingerprintdata against all of the registered fingerprint data sets belonging tothe verification object group has been completed (when YES is selectedin step S57), the verification processing section 11 d (21 d) determineswhether or not the final highest score held in the step S56 is equal toor higher than a given score which enables identification of the subjectof authentication; that is, whether or not the fingerprint of thesubject of authentication is the fingerprint of the registrant of theregistered fingerprint data having acquired the highest score (stepS60).

When in step S60 the fingerprint is determined to be the fingerprint ofthe authenticated person (when YES is selected), the fingerprint dataset matching the verification fingerprint data is specified among theplurality of registered fingerprint data (the verification objectgroup). The verification result indicating that the subject ofauthentication is the registrant is output from the verification resultoutput section 13 (23) (step S61), and verification processing isterminated.

When in step S60 the final highest score held in step S56 is determinedto be less than the predetermined score (when NO is selected), theregistered fingerprint data set coinciding with the verificationfingerprint data cannot be specified among the verification objectgroup. The held highest score is discarded, and a signal indicating thatthe fingerprint of the subject of authentication is not registered asregistered fingerprint data (identification has ended in failure) isoutput from the verification result output section 13 (23) (step S62),and verification processing is completed.

As mentioned previously, according to the verification procedures shownin FIG. 15, the verification fingerprint data are verified against allof the registered fingerprint data sets belonging to the verificationobject group. When the registered fingerprint data set that has beenacquired as a result of verification and has the highest degree ofcoincidence satisfies the predetermined verification standards, theregistered fingerprint data are authenticated as belonging to thesubject of authentication, and the subject of authentication isidentified as the registrant.

In the case of general verification of a fingerprint, the degree ofcoincidence is represented as a score as mentioned previously. When thescore is higher than a given score, the subject of authentication isidentified. According to the verification procedures shown in FIG. 12,verification is performed in accordance with the verification prioritylevels. When verification has attained success, the subject ofauthentication is identified as the authenticated person. Therefore, ascompared with a case where verification is performed at random on around-robin basis, the probability of the specified registeredfingerprint data being the fingerprint of the authenticated person isconsiderably high. However, there still exists a small chance of thespecified registered fingerprint data being identified as belonging toanother person.

Therefore, according to the verification procedures shown in FIG. 15,the registered fingerprint data are grouped, and the group having thehighest verification priority level is taken as a verification objectgroup. The registered fingerprint data set having the highest score inthe verification object group is specified as belonging to the subjectof authentication, thereby considerably diminishing the chance ofanother person being erroneously identified.

[3-5] Modification of Verification Priority Level Computation Procedures

By reference to FIGS. 16 to 18, a modification of the verificationpriority level computation procedures of the present embodiment; thatis, procedures for sorting the registered fingerprint data in step S50shown in FIG. 15 which are performed by the function of theregistration-purpose data read control section 11 c (21 c) serving asthe verification priority level computation section, will be describedin greater detail.

As shown in FIG. 17, data analogous to those described in connectionwith the embodiments shown in FIGS. 5, 13, and 14 are registered in theregistration-purpose data storage section 15 b (25 b). Specifically, theregistered fingerprint data set (fingerprint data set 1, fingerprintdata set 2, and fingerprint data set 3), the attribute information “a”(e.g., a pattern type: attributes a1, a2, and a3), theregistration-purpose attribute information “b” (e.g., the number offeature points; attributes b1, b2, and b3), and the registration-purposeattribute information “c” (e.g., moisture content; attributes c1, c2,and c3) are registered in association with the IDs (ID1, ID2, and ID3)of the respective fingerprint registrants. As shown in FIG. 17,weighting coefficients 2, 1, 3 are previously imparted to theregistration-purpose attribute information items “a,” “b,” and “c.”These weighting coefficients are determined in consideration of thedetection accuracy of the respective attribute information items,variations in data, or the like.

Procedures for sorting the registered fingerprint data will be describedin accordance with the flowchart shown in FIG. 16 (steps S71 to S75).First, attribute information about the first priority level item (theattribute information “b” in the embodiment shown in FIG. 17) is readfrom the registration-purpose data storage section 15 b (25 b) (stepS71). A determination as to coincidence/noncoincidence is rendered bycomparing the verification-purpose attribute information “b” with theregistration-purpose attribute information items “b1, b2, and b3” (stepS72). The registered fingerprint data are sorted on the basis of theresult of determination (step S73).

Subsequently, a determination is made as to whether or not the item ofthe attribute information which has been subjected to coincidencedetermination is the final item (the item having the lowest prioritylevel) (step S74). When the item is not the final item (when NO isselected in step S74), attribute information about the item of nextpriority level is read from the registration-purpose data storagesection 15 b (25 b) (step S75). Processing analogous to that mentionedpreviously is repeatedly performed (steps S72 to S74). When in step S74the item of the attribute information is determined to be the final item(when YES is selected in step S74), sorting operation is completed.

By means of such a sorting operation, in the embodiment shown in FIG. 17the groups are classified into a group (fingerprint data sets 2 and 3)for which a coincidence exists between the verification-purposeattribute information “b” and the registration-purpose attributeinformation items b1, b2, and b3 and a group (fingerprint data set 1)for which no coincidence exists between the verification-purposeattribute information “b” and the registration-purpose attributeinformation items b1, b2, and b3. Next, the group (the fingerprint dataset 2 and 3) for which a coincidence exists between theverification-purpose attribute information “b” and theregistration-purpose attribute information items is further classifiedinto a group (the fingerprint data 2) for which a coincidence existsbetween the verification-purpose attribute information “a” and theregistration-purpose attribute information a2, a3 and a group (thefingerprint data 3) for which a coincidence does not exist between theverification-purpose attribute information “a” and theregistration-purpose attribute information a2, a3. As a result, theattribute information items are sorted in such an order as shown in FIG.17. The highest group includes the fingerprint data set 2; the secondgroup includes the fingerprint data set 3; and the third group includesthe fingerprint data set 1. Even in FIG. 17, underlined attributes aretaken as coinciding with the verification-purpose attribute informationitems.

In the embodiment shown in FIG. 17, the number of registered fingerprintdata sets is only three. Therefore, the registered fingerprint data setsare classified into three groups. However, in a case where a pluralityof registered fingerprint data sets are registered, the data areclassified into a maximum of eight groups, as shown in FIG. 18. In FIG.18, as in the case of the embodiment shown in FIG. 17, three types ofregistration-purpose attribute information items “a,” “b,” and “C” areassumed to be associated with the registered fingerprint data sets, andpriority levels 2, 1, and 3 are assumed to be previously assigned to theregistration-purpose attribute information items “a,” “b,” and “C.”Under these assumptions, the highest group is a group of registeredfingerprint data sets for which all of the attribute information items“a,” “b,” and “c” have coincided with the verification-purpose attributeinformation; the second group is a group of registered fingerprint datasets for which the two attribute information items “a” and “b” havecoincided with the verification-purpose attribute information; a thirdgroup is a group of registered fingerprint data sets for which the twoattribute information items “b” and “c” have coincided with theverification-purpose attribute information; a fourth group is a group ofregistered fingerprint data sets for which only the attributeinformation item “b” has coincided with the verification-purposeattribute information; a fifth group is a group of registeredfingerprint data sets for which the two attribute information items “a”and “c” have coincided with the verification-purpose attributeinformation; a sixth group is a group of registered fingerprint datasets for which only the attribute information item “a” has coincidedwith the verification-purpose attribute information; a seventh group isa group of registered fingerprint data sets for which only the attributeinformation item “c” has coincided with the verification-purposeattribute information; and an eighth group is a group of registeredfingerprint data sets for which no attribute information has coincidedwith the verification-purpose attribute information.

Grouping operations may first be performed by means of the function ofthe verification priority level computation section, and theverification processing section 11 d (21 d) may select only the highestgroup as a verification object group or select the plurality of highergroups as verification object groups.

[4] Modification of the Fingerprint Data Verification Apparatus

FIG. 19 is a block diagram showing the functional configuration of amodification of the fingerprint data verification apparatus (thebiometric information verification apparatus) of the present embodiment.The fingerprint data verification apparatus shown in FIG. 19 isconfigured in substantially the same manner as is the fingerprint dataverification apparatus shown in FIG. 2. However, the fingerprint dataverification apparatus shown in FIG. 19 is further provided with anattribute information change section 11 f (21 f) and a data managementsection 11 g (21 g).

Unparenthesized reference numerals in FIG. 19 and the followingdescriptions are assigned to the functional configurations realized bythe hardware configuration (the fingerprint authentication apparatus 10)shown in FIG. 3. Parenthesized reference numerals are assigned to thefunctional configuration realized by the hardware configuration (thefingerprint authentication system) shown in FIG. 4. Further, thefunction of the attribute information change section 11 f (21 f and thefunction of the data management section 11 g (21 g) are realized bymeans of the CPU 11 (21) executing the fingerprintregistration/verification program 15 a (the fingerprint verificationprogram 25 a).

Now, the attribute information change section 11 f (211 f acts as achange section capable of changing or updating the registration-purposeattribute information in the registration-purpose data storage section15 b (25 b) to the verification-purpose attribute information extractedby the verification-purpose attribute information extracting section 11b (21 b) when the verification processing section 11 d (21 d) hasspecified the registered fingerprint data set coinciding with theverification fingerprint data among the plurality of registeredfingerprint data sets (when verification has attained success and thesubject is identified).

Of the attribute information items, some have universal properties(e.g., a pattern type or the number of feature points) and some changein accordance with the circumstances (e.g., a moisture content of thefinger surface or input environment information). For this reason, whenthe attribute value has changed at the time of verification from thatacquired during registration, the attribute information change section11 f (21 f) changes or updates the registration-purpose attributeinformation in the registration-purpose data storage section 15 b (25 b)to a value obtained during verification, thereby enhancing thedetermination accuracy of the verification priority level further.However, as mentioned previously, such change or updating operation isperformed limitedly when verification has attained success and thesubject is identified.

Here, the data management section 11 g (21 g) functions as a managementsection which manages and monitors the number of registered fingerprintdata sets in the registration-purpose data storage section 15 b (25 b)and changes the number of types of registration-purpose attributeinformation verification-purpose attribute information used when theregistration-purpose data read control section 11 c (21 c) computes theverification priority level in accordance with the number of registeredfingerprint data sets.

When the number of registered fingerprint data sets registered in theregistration-purpose data storage section 15 b (25 b) is small, theremay be a case where the processing time required to compute theverification priority levels using the attribute information itemsaccounts for a large proportion of the total time required byverification processing. For this reason, the data management section 11g (21 g) controls the number of types of attribute information itemsused for computing the verification priority levels, in accordance withthe number of registered fingerprint data sets, thereby optimizing theprocessing time. Specifically, when the number of registered fingerprintdata sets is small, the number of types of attribute information usedfor computing the verification priority levels is reduced.

[5] Advantage of the Present Embodiment

According to the fingerprint data registration apparatus, thefingerprint data verification apparatus, and the fingerprintauthentication system, all belonging to the previously-describedembodiments, when one-to-many authentication is performed using afingerprint image, the verification priority levels of the plurality ofregistered fingerprint data sets are computed on the basis of theplurality of types of registration-purpose attribute informationassociated with the respective registered fingerprint data sets and theplurality of types of verification-purpose attribute information itemsextracted from the fingerprint image of the subject of authentication.In accordance with the computed verification priority levels, thefingerprint data extracted from the fingerprint image of the subject ofauthentication are sequentially verified against the registeredfingerprint data sets, and the registered fingerprint data setcoinciding with the verification fingerprint data is specified among theplurality of registered fingerprint data sets.

As mentioned above, when the registered fingerprint data sets have thehigher verification priority level determined on the basis of theplurality of types of attribute information items, the probability ofthe registered fingerprint data coinciding with the fingerprint datapertaining to the subject of authentication is high. Accordingly, evenif the verification fingerprint data are not verified against all of theregistered fingerprint data sets on a round-robin basis when one-to-manyauthentication is performed, the registered fingerprint data setpertaining to the subject of authentication can be determined, so longas verification is performed in accordance with the verificationpriority levels and a certain degree of coincidence is achieved. Thetime (number of verification operations) required to effect verificationprocessing can be significantly diminished, and verification accuracycan be enhanced.

When randomly-sorted registered fingerprint data sets are sequentiallyused for verification as in the related art, there still exists a chanceof erroneous verification (verification which allows erroneousacceptance of verification fingerprint data of another person), andhence the subject is identified only when the degree of coincidenceobtained as a result of verification—for which the level of verificationstandards is set considerably high—as exceeded the level or when theregistered fingerprint data set that has the highest degree ofcoincidence after the verification fingerprint data have been verifiedagainst all of the registered fingerprint data sets on a round-robinbasis is specified as belonging to the authenticated person. In theformer case, the subject can be reliably identified when the level ofverification standards has been exceeded the verification standards.However, when the level of the verification standards is too high, thepossibility of a failure in authentication is high and not practical. Inthe latter case, the verification fingerprint data must be verifiedagainst all of the registered fingerprint data sets, and verificationprocessing involves consumption of too much time.

In contrast, according to the present embodiment, when one-to-manyfingerprint authentication is performed, the verification fingerprintdata are verified against the registered fingerprint data sets indecreasing sequence of registered fingerprint data having a highprobability of coincidence, in accordance with the verification prioritylevels determined by the plurality of attribute information items.Hence, the time (the number of verification operations) required forverification processing can be curtailed to a great extent. Practicalpersonal authentication can be performed with a considerably high degreeof accuracy, depending on the fingerprint data and the plurality ofattribute information items.

Further, as mentioned previously, when the verification procedures suchas those shown in FIG. 15 are used, the registered fingerprint data setsare grouped, and the group having the highest verification prioritylevel is taken as a verification object group, and the registeredfingerprint data set having the highest score in the verification objectgroup is specified as belonging to the subject of authentication. Hence,the possibility of erroneous authentication of another person can bedrastically diminished, to thus enhance verification accuracy.

[6] Others

The present invention is not limited to the previously-describedembodiment but can be carried out while being modified in variousmanners within the scope of the gist of the present invention.

For instance, the previous embodiments have described a case where thebiometric information is a fingerprint image. However, the presentinvention is not limited to the embodiments. Even when the biometricinformation is a palm pattern, an iris (iris muscle pattern), a voice, afacial image, a vascular pattern (a retinal vascular pattern, or a veinpattern), a dynamic signature, or a keystroke, the present invention isapplied in the same manner as mentioned previously. Thereby, the sameworking-effect as that achieved in the previously-described embodimentcan be acquired.

The previously-described embodiment has described the case where theplurality of attribute information items are three types: for instance,a pattern type, the number of feature points, and a moisture content.However, the present invention is not limited to this embodiment. Solong as two or more of the previously-described (1) to (7) attributeinformation items are used, the same working-effect as that yielded inthe previously-described embodiment can be acquired.

Here, a determination as to coincidence/noncoincidence between theattribute information items is performed in reality as follows. Adetermination as to whether or not the pattern type and the inputenvironment information has achieved a coincidence is made on the basisof whether or not the verification-purpose attribute information and theregistration-purpose attribute information coincide perfectly. Adetermination as to whether or not the shapes “x” and “y” coincide witheach other is determined on the basis of whether or not a differencebetween the verification-purpose shapes “x” and “y” and theregistration-purpose shapes “x” and “y” falls within a predeterminedrange or whether or not a difference between the ratio of theverification-purpose shape “x” to the verification-purpose shape “y” andthe ratio of the registration-purpose shape “x” to theregistration-purpose shape “y” fall within a predetermined range. Adetermination—as to whether or not a coincidence is acquired in terms ofthe number of feature points, the volume of data, a processing time, andthe moisture content of a finger surface—is made on the basis of, e.g.,whether or not a difference between the verification-purpose attributevalues and the registration-purpose attribute values falls within apredetermined range.

INDUSTRIAL APPLICABILITY

As mentioned above, according to the present invention, verification isperformed in accordance with verification priority levels although theverification-purpose feature information is not verified against all ofthe registration-purpose feature information items on a round-robinbasis when one-to-many authentication is performed using biometricinformation. If a certain degree of coincidence is acquired, theregistration-purpose feature information about the subject ofauthentication can be determined. Thereby, the time required toverification processing (the number of verification operations) can besignificantly diminished, and the verification accuracy can also beenhanced.

Therefore, the present invention is considered to be suitable for usewith a system which authenticates the identity of a person by means ofbiometric information; for example, a fingerprint, a palm pattern, aniris, a voice, a facial image, a vascular pattern, a dynamic signature,or a keystroke, and to be considerably-highly useful.

1. A method for registering biometric information, comprising: (a)sampling, from a registered subject, registration-purpose biometricinformation to be used for one-to-many authentication and inputting thesampled information; (b) extracting registration-purpose featureinformation from the registration-purpose biometric information input insaid step (a) of sampling; (c) extracting, from the registration-purposebiometric information input in said step (a) of sampling, a plurality oftypes of registration-purpose attribute information differing from theregistration-purpose feature information; and (d) registering theregistration-purpose feature information extracted in said step (b) ofextracting and said plurality of types of registration-purpose attributeinformation extracted in said step (c) of extracting in associated withone another.
 2. The method for registering biometric informationaccording to claim 1, further comprising storing theregistration-purpose feature information and the plurality of types ofregistration-purpose attribute information, which are registered inassociation with one another in said step (d) of registering.
 3. Themethod for registering biometric information according to claim 1,wherein the registration-purpose biometric information sampled and inputin said step (a) of sampling comprise a fingerprint image from theregistered subject; the registration-purpose feature informationextracted from the fingerprint image in said step (b) of extractingcomprises information about at least feature points of ridges of thefinger print image; and the registration-purpose attribute informationextracted in said step (c) of extracting comprises at least two of apattern type of a fingerprint of the fingerprint image, the geometry ofa finger of the fingerprint image, the number of the feature points, thevolume of data pertaining to the feature information, a processing timerequired in said step (b) of extracting to extract information about thefeature points, the quantity of moisture on the surface of the finger inthe fingerprint image, and input environment information of thefingerprint image.
 4. A method for verifying biometric information,comprising: (a) sampling, from a subject of authentication,verification-purpose biometric information to be used for one-to-manyauthentication and inputting the sampled information; (b) extractingverification-purpose feature information from the verification-purposebiometric information input in said step (a) of sampling; (c)extracting, from the verification-purpose biometric information input insaid step (a) of sampling, a plurality of types of verification-purposeattribute information differing from the verification-purpose featureinformation; (d) computing verification priority levels of a pluralityof registration-purpose feature information items to be verified againstthe verification-purpose feature information extracted in said step (b)of extracting, on the basis of a plurality of types ofregistration-purpose attribute information associated with the pluralityof registration-purpose feature information items and the plurality oftypes of verification-purpose attribute information extracted in saidstep (c) of extracting; and (e) verifying said verification-purposefeature information extracted in said step (b) of extractingsuccessively against the plurality of registration-purpose featureinformation items in accordance with the verification priority levelscomputed in said step (d) of computing, to thus specify information,which coincides with said verification-purpose feature information, fromamong the plurality of registration-purpose feature information items.5. The method for verifying biometric information according to claim 4,wherein said step (d) of computing comprises: comparing the plurality oftypes of verification-purpose attribute information with the pluralityof types of registration-purpose attribute information associated withthe respective registration-purpose feature information items, to thusdetermine whether or not a coincidence exists between said informationitems; summing, for each said registration-purpose feature informationitem, weighting coefficients previously assigned to registration-purposeattribute information, which is determined to coincide with theverification-purpose attribute information, among said plurality oftypes of registration-purpose attribute information associated with theregistration-purpose feature information items, to thus compute a sumvalue of the weighting coefficients as an attribute informationcoincidence score pertaining to said registration-purpose featureinformation items; and determining the verification-purpose prioritylevels in accordance with said attribute information coincidence scores.6. The method for verifying biometric information according to claim 4,wherein said step (d) of computing comprises: comparing the plurality oftypes of verification-purpose attribute information with the pluralityof types of registration-purpose attribute information associated withthe respective registration-purpose feature information items, to thusdetermine whether or not a coincidence exists between said informationitems; and determining the verification priority levels in accordancewith a priority level previously assigned to said information, which isdetermined to coincide with the verification-attribute information,among the plurality of types of registration-purpose attributeinformation.
 7. The method for verifying biometric information accordingto claim 4, wherein said step (e) of verifying comprises: completingverification of the verification-purpose feature information against therespective registration-purpose feature information items at a point intime when a registration-purpose feature information item, whichcoincides with the verification-purpose feature information whilesatisfying a predetermined standard, appears; and specifying theregistration-purpose feature information item satisfying thepredetermined standard as information coinciding with theverification-purpose feature information.
 8. The method for verifyingbiometric information according to claim 4, wherein said step (e) ofverifying comprises: grouping, as a verification object group,registration-purpose feature information items whose verificationpriority levels computed in said step (d) of computing are higher than areference level; verifying the verification-purpose feature informationagainst all of registration-purpose feature information items belongingto the verification object group; and specifying, in accordance with aresult of said verification, a registration-purpose feature informationitem having the highest coincidence as information coinciding with theverification-purpose feature information.
 9. The method for verifyingbiometric information according to claim 4, further comprising changingor updating said registration-purpose attribute information to theverification-purpose feature information extracted in said step (c) ofextracting when information coinciding with the verification-purposefeature information has been specified from among the plurality ofregistration-purpose feature information items in said step (e) ofverifying.
 10. The method for verifying biometric information accordingto claim 4, further comprising managing the number of saidregistration-purpose feature information items and changing, inaccordance with the number, the number of types of saidregistration-purpose attribute information/said verification-purposeattribute information used when verification priority levels arecomputed in said step (d) of computing.
 11. A method forregistering/verifying biometric information, comprising: (a) sampling,from a registered subject, registration-purpose biometric information tobe used for one-to-many authentication and inputting the sampledinformation; (b) extracting a registration-purpose feature informationitem from the registration-purpose biometric information input in saidstep (a) of sampling; (c) extracting, from the registration-purposebiometric information input in step (a) of sampling, a plurality oftypes of registration-purpose attribute information differing from theregistration-purpose feature information item; (d) registering theregistration-purpose feature information item extracted in said step (b)of extracting and said plurality of types of registration-purposeattribute information extracted in said step (c) of extracting inassociation with one another; (e) storing, in a registration-purposedata storage section, the registration-purpose feature information itemand the plurality of types of registration-purpose attributeinformation, which are registered in an associated with one another insaid step (d) of registering; (f) sampling, from a subject ofauthentication, verification-purpose biometric information to be usedfor one-to-many authentication and inputting the sampled information;(g) extracting verification-purpose feature information from theverification-purpose biometric information input in said step (f) ofsampling; (h) extracting, from the verification-purpose biometricinformation input in said step (f) of sampling, a plurality of types ofverification-purpose attribute information differing from theverification-purpose feature information; (i) computing verificationpriority levels of a plurality of the registration-purpose featureinformation items which are stored in said step (e) of storing in theregistration-purpose data storage section to be verified against theverification-purpose feature information extracted in said step (g) ofextracting, on the basis of the plurality of types ofregistration-purpose attribute information, associated with theplurality of registration-purpose feature information items and theplurality of verification-purpose attribute information extracted insaid step (h) of extracting; and (j) verifying the verification-purposefeature information extracted in said step (g) of extracting against theplurality of registration-purpose feature information items inaccordance with the verification priority levels computed in said step(i) of computing, to thus specify information, which coincides with theverification-purpose feature information, from among the plurality ofregistration-purpose feature information items.
 12. The method forregistering/verifying biometric information according to claim 11,wherein said step (i) of computing comprises: comparing the plurality oftypes of verification-purpose attribute information with the pluralityof types of registration-purpose attribute information associated withthe respective registration-purpose feature information items, to thusdetermine whether or not a coincidence exists between said informationitems; summing, for each said registration-purpose feature informationitem, weighting coefficients previously assigned to registration-purposeattribute information, which is determined to coincide with theverification-purpose attribute information, among the plurality of typesof registration-purpose attribute information associated with theregistration-purpose feature information items, to thus compute a sumvalue of the weighting coefficients as an attribute informationcoincidence score pertaining to the registration-purpose featureinformation items; and determining the verification-purpose prioritylevels in accordance with said attribute information coincidence score.13. The method for registering/verifying biometric information accordingto claim 11, wherein said step (i) of computing comprises: comparing theplurality of types of verification-purpose attribute information withthe plurality of types of registration-purpose attribute informationassociated with the respective registration-purpose feature informationitems, to thus determine whether or not a coincidence exists betweensaid information items; and determining the verification priority levelsin accordance with a priority level previously assigned to saidinformation, which is determined to coincide with theverification-attribute information, among the plurality of types ofregistration-purpose attribute information.
 14. The method forregistering/verifying biometric information according to claim 11,wherein said step (j) of verifying comprises: completing verification ofthe verification-purpose feature information against the respectiveregistration-purpose feature information items at a point in time when aregistration-purpose feature information item, which coincides with theverification-purpose feature information while a satisfyingpredetermined standard, appears; and specifying the registration-purposefeature information items satisfying the predetermined standards asinformation coinciding with said verification-purpose featureinformation.
 15. The method for registering/verifying biometricinformation according to claim 11, wherein said step (j) of verifyingcomprises: grouping, as a verification object group,registration-purpose feature information items whose verificationpriority levels computed in said step (i) of computing are higher than areference level; verifying the verification-purpose feature informationagainst all of registration-purpose feature information items belongingto the verification object group; and specifying, in accordance with aresult of said verification, a registration-purpose feature informationitem having the highest coincidence as information coinciding with theverification-purpose feature information.
 16. The method forregistering/verifying biometric information according to claim 11,further comprising changing or updating the registration-purposeattribute information in the registration-purpose data storage sectionto the verification-purpose feature information extracted in said step(h) of extracting when information coinciding with theverification-purpose feature information has been specified from amongthe plurality of registration-purpose feature information items in saidstep (j) of verifying.
 17. The method for registering/verifyingbiometric information according to claim 11, further comprising managingthe number of said registration-purpose feature information items andchanging, in accordance with the number, the number of types of theregistration-purpose attribute information/said verification-purposeattribute information used when verification priority levels arecomputed in said step (i) of computing.